Shade-holder



D. WOODHEAD.

I SHADE HOLDER.

, APPLICATION FILED FEB. 21. 1918.

Patented July 15, 1919.

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DANIEL WOODHEAD, 0F EVANSTON', ILLINOIS.

SHADE-HOLDER.

Specification of Letters Patent.

Patented July I5, 1919.

Application filed February 21, 1918. Serial No. 218,388.

To all whom, it mag concern:

Be it known that I, DANIEL WOODHEAD, a citizen of the United States, residing at Evanston, in the county of Cook and State of Illinois, have invented a certain new and useful Improvement in Shade-Holders, of which the following is a specification.

My invention relates to shade holders for use in connection with electric lamps, and the object of the invention is to provide a screw shade holder which, upon being screwed home, will automatically lock itself, but will automatically unlock itself when a moderate torsional strain is exerted by the operator in a direction to unscrew the device.

I accomplish this object by the construction shown in the accompanying drawing, in which:

Figure 1 is an axial section of the shade' holder and associated parts showing the lamp in position.

Flg. 2 is a perspective view of the two principal parts of the shade holder illustrating the manner in which they go together and the locking means by which they are prevented from accidentally becoming separated from each other.

Fig. 3 is a bottom plan section of the internally threaded part on a line 33, Fig. 1.

Fig. 4 is a sectional view on the line H, Fi 3.

Similar numerals refer to similar parts throughout the several views.

In the illustrated form selected to explain the principle of the invention, the shade .1 may be of any suitable type. It is here indicated as being of sheet metal and being permanently fastened to the part 2 of the shade holder. Said part 2 is cylindrical and is screw-threaded at its upper end to screw into the part 3. Part 3 is illustrated as being of cast metal and adapted to support the lamp socket 4: which receives the lamp 5. Parts 2 and 3 are provided respectively with inwardly projecting flanges 7 and 8 which abut each other when the device is assembled. In the particular form illustrated, flange 8 has a rounded boss 10 adapted to fit into anyone of the depressions or sockets 11 formed in flange 7 Flange 7 is resilient and the result is that when the part 2 is screwed to the limit in the part 3,

ing accidentally unscrewed. It will be understood that in industrial buildings there is frequently a good deal of jarring, and

this has a tendency to unscrew the ordinary screw fixture. My device, however, overcomes this' tendency for, as the flange 7 is resilient, the sockets 11 snap into engagement with boss 10 and thus form an impositive lock, which is quite adequate to prevent accidental rotation but readily permits an operator to unscrew the parts when necessary.

It will be understood, of course, that sockets 11 in flange 7 may be mere depressions, or they may be actual apertures, the action being the same in either event, as the bosses 10 are rounded and act somewhat after the manner of cams to force the flange 7 to disengage when the operator deliberately applies enough force to unscrew the parts.

It will be observed that the parts are extremely simple as well as efficient, for the part 3 may be a simple casting and part 2 a one-piece sheet metal element which may be convenientl formed by spinning or by suitable dies. he construction is also dura' ble, and as there are but two parts in the entire device, there are no screws to be lost or damaged and no clamps or other locking devices of a more complicated nature required.

Attention is called to my co-pending application S. N. 218,387 for shade holders, filed on even date herewith.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is

A shade holder comprising a hollow supporting member having an interior flange spaced from its lower end, a shade holding member threaded in the lower end of the supporting member and movable into abuttin relation to the flange, and cotiperating locking elements on the flange and the adjacent end of the shade holding member yieldingly holding said members against relative rotation.

In witness whereof I have hereunto subscribed my name.

DANIEL WO ODI-IEAD.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents.

Washington, D. G. 

